Local officials are now knee-deep in a $125,000 study to discover the underground shape of the dwindling West Plains aquifer.
The vast aquifer is being depleted because it can’t naturally recharge itself as fast as cities are growing, say Department of Ecology and Spokane County officials.
Officials just wrapped up the first phase of the geophysical study, in which they tested to find the best method of measuring the various basalt layers that make up this 12,000-year-old water resource.
With this method in hand, workers will begin searching for new places to drill wells, said Rob Lindsay, water resources manager for Spokane County.
“We feel that having a better understanding of the (underground basalt) relationships will help us identify areas of additional water,” Lindsay said.
Airway Heights’ and Medical Lake’s water supplies have been slowly dropping off over the years as they draw from the aquifer. The two cities also have some wells placed close together, and the use of one occasionally draws down the level of the other city’s well.
Stakeholders in the geophysical study, carried out by Spokane County, want to explore the underground shape of the aquifer to find new places for drilling. The aquifer may have new pockets of undiscovered groundwater under the West Plains.
With the study money, Lindsay said they are considering building a groundwater monitoring well, which would help measure the water regularly.
Officials are also searching for a candidate site for an aquifer storage and recovery project, a piece of land where water can be pumped into from another source and drain into the ground, where it will reliably stay until needed.
“We can store that water in the ground naturally for later use,” Lindsay said. Due to the dropping water line, a water pipe from the city of Spokane was built out to the West Plains last summer, and Airway Heights now pays the city for its use. Medical Lake is currently in negotiations with Spokane to use the pipe.
The pipe runs out to the corner of Highway 902 and Craig Road, said Spokane water officials, and another section of piping will soon run to Fairchild Air Force Base.
And it’s not just cities that are slowly draining the aquifer, said Medical Lake city administrator Doug Ross.
“There’s this idea we’re gluttonous with our water,” Ross said.
Many people, particularly large agricultural farmers, live outside city limits and draw from their own domestic wells, Ross said. As more people move onto the West Plains, these people use more water – a factor that is also depleting the aquifer.
“I just don’t want people to think the sole problem is a municipality,” he said.
Airway Heights has a $42 million wastewater treatment plant in the works, a facility that would pump about half a million gallons of reused water back into the aquifer. Airway Heights officials hope the reused water can help boost the natural water supply.